Axial disc brake



Nov. 27, 1956 e. M. DAVEY 2,771,966

AXIAL DISC BRAKE Filed April 5, 1954 2 Sheets-Sheet l "III/111111111114 INVEN TOR. 650/265 M 0/1 1 5) Nov. 27, 1956 e. M. DAVEY I 5 AXIAL DISC BRAKE FiledApril 5, 1954 2 Sheets-Sheet 2 8L6 .Mmzw

ATTOF/VEY United States Patent AXIAL DISC BRAKE George M. Davey, Downey, Calif., assignor to Hadco Engineering Co., Inc., Huntington Park, Calif., a corporation of California Application April 5, 1954, Serial No. 420,810

10 Claims. Cl. 188-72) This invention relates to a brake construction more particularly adapted for heavy duty installations as on truck wheels, although the same may be' adapted for general use on vehicle wheels. More specifically, the invention deals with a power-operated brake construction of the disc type.

One of the primary factors in any brake construction is the braking area, i. e., the amount of brake lining surface that is applied to the brake drum. All else being equal, the larger such area, the more powerful are the brakes. However, particularly in brakes that apply the lined brake shoes to the inner cylindrical wall of the brake drum, there are practical limits to the drum diameter and the width of the brake shoes, these limits being controlled by wheel sizes and tire tread widths.

The braking area can be materially, increased and yet keep the diametral and width dimensions of the brake within proper limits, by a twin disc construction, and it is an object of the present invention to provide a twin disc brake of novel and improved form.

Another factor in brake efiiciency is temperature generation during braking. Another object of this invention is to provide a novel brake structure that is self air cooled to improve braking power and reduce the wear on the brake lining.

A further object of the invention is to provide a twin disc brake that embodies a novel interconnecting arrangement of members which engage the brake shoes to provide a powerful, yet somewhat elastic, braking operation that results in rapid yet smooth vehicular stops.

The invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawings merely show and the following description merely describes, one embodiment of the present invention, which is given by way of illustration or example only. i

In the drawings, like reference characters designate similar parts in the several views. 1

Fig. 1 is a cross-sectional view of a brake according to the present invention and shown in operative position mounted within a wheel felly.

Fig. 2 is a face view of the brake with parts broken away in successive stages. a

. Fig. 3 is a cross-sectional view of the brake taken at right angles to the line of section of Fig. 1.

The power brake that is illustrated is shown in its normal position of installation in a wheel 5 which, in this instance, is shown as a dual wheel. The brake is shown housed within the hollow of the inner wheel, 6 which, in the usual manner is removably attached, as by bolts 7, to the rotating hub 8 on the spindle thatprotrudes from the conventional fixed axle 9.

2,771,966 Patented Nov. 27, 1956 The brake that is illustrated comprises, generally, a

' backing plate 10 fixedly secured to a flange 11 on axle 9 as by bolts 12, a front pressure plate 13 outwardly spaced from backing plate 10, a center ring 14 between said plates 10 and 13, link means 15 interconnecting said plates and ring, similar braking discs 16 and 17 disposed respectively between plate 10 and ring 14, and plate 13 and ring 14, a housing drum 18 fastened to spindle 8 by the mentioned bolts 7, sliding key connection means 19 non-rotationally interconnecting the braking discs 16 and 17 and drum 18, pressure means 20 operable to move the front plate 13 toward backing plate 10 and, thereby, apply braking force to the brake, and cooling means 21 embodied in the drum 18, the outer plate 13 and the center ring 14 to establish a circulation of cooling air among the several brake elements during application of the brake to cool the brake assembly.

The backing plate 10 preferably comprises a metal casting that is provided with an outwardly directed annular face 22. In order that said plate be substantially rigid, so as not to flex under pressure applied to said face, the same is formed to have an annular rearward stiffening flange 23 and a dished annular portion 24 inwardly of face 22 and suitable ribs 25 radially across said dished portion. In this or in a comparable manner, said plate 10 is made to strongly resist deflection under braking force.

The front pressure plate 13 also preferably comprises a metal casting and is of the same diametral size as plate 10. Plate 13 is formed as a ring having an inwardly directed annular face 26 and is provided with outwardly directed annular ribs or fins 27 which not only render said plate substantially inflexible but serve also as cooling.

fins and, therefore, are part of the cooling means 21. On each side, said plate 13 is preferably integrally provided with a rigidifying brace 28 that also has the purpose of providing pivot bearings 29a for the pressure means 20. The bearings are aligned on a diametral line of said plate.

As shown, plates 10 and 13 are concentrically arranged on the axis of axle 9 and with their respective faces 22 and 26 in opposed relation.

The center ring 14 is provided with opposed side faces 29 and 30 and is of the same diametral size as plates 10 and 13, the face 29 being in opposition to face 22 and the face 30 in opposition to face 26. Said'ring is provided with a plurality of radial air passages 31 that are also part of the cooling means 21.

The link means 15 interconnecting plates 10 and 13'- and ring 14 comprises a set of equally spaced bearing bosses 32 formed integrally on backing plate 10, a second set of similarly spaced bearing bosses 33 formed integrally on front pressure plate 13, a third set of similarly spaced bearing bosses 34 formed integrally. on the center ring 14 and extending outwardly from the ring on each side thereof, and pairs of laterally flexible links 35 interconnecting the three sets of bosses.

In this instance, each set of bosses 32, 33 and 34 comf boss 33 on the other side of said ring. Thus, the pres-' sure plate 13 and center ring 14 are connected to fixed backing plate 10 by means of against rotation.

It will be noted that the links 35 are slightly bent so that the ends thereof are offset, as shown in Fig. I Thus,

the links 35 and are-held:

whema pairoflinks' aresecured to vbosses 34, the ends 7 thereof. secured. to. said. bosses are. spaced closes together than the ends secured to bosses 32 and 33. In this manner ,the links space the braking elements so that the res ectivezpairszefirraeeszzz: andlw pand wantmtrrespectively accommodate :brakihg dises 11mm 17 tiieiebetweeirwitheuf: frictional: en agement With said? dis'es';

braking: disc 16 anfd 1 7 cdnip'ri'ses a meta? ring Siandahrakeihing orif'aeing: 3 7'- on eaeh s'ide-of said ring; s'afid lining being secured in place; as by'- rivets} 38*:-

Theh'ousing drum-=13 is rotationalwith spindle housing 8' and; therefore; with wheel's: Said drumprefer-ably comprises metal castinghaving a: cylindrical; fian' e 39 withinzwhich the plate-13;- ring'wa'nd hra ng dises ifi and; 17 arezlieused- In" anysuit'able'por-tionof itsperipli' enygtas'sat the outer portions'tl'iereof', said dr'i'im is-formed withta suitable number ofiaifisbbbps iti' tliatare formedas" louvre's which co'llectair' duringrotationof the wheel and direct the same intb' the interior of the drum throu h openings t l immediately adja'centisaid"scoops All of the scoops maybe in the same direction; that'of normal for ward rotation of the wheel," or' some may be in one direction and some in" the other soth'at air is drawnint'o thehousing drum-regardless of thedirection of rotation ofithe wlieell Said scoops 40 and open'ings' 4E also form part-of? the cooling means 21." V

The connection means 19compri'ses a series of prefer ably uniformly spaced spline seats 42in the inner 'fa'ce of" drumi flange 39; the same extending outwardly'fromthe':inwardly directed edge of said flange, and a set of splines 43 on the outer peripheral edge offigilite iiti of cach braking disc- 16 and 17-. Said splines- 43 slidingly fit'lthe'ispline' seats 42 so that discs 16 and I7 areprotatio'nallykeye'd' to drum flange 39 and yet are adapt'ed to'i slide-laterally as will later be seen.

Airr'outlet passages 44, als'opart of the coo'lingrneans 2:1, Iareiformed indiam flange 3 9"and--extend from spline" seats "42 to the outer periphery of said flange.

The' pre'ssure means-20 m shown'as anarrn45 mo'unted on a'pivot 46 ina boss '47 integrally=formedonbaclciiig plate 10' and inwardly ofthe'housing drum 1 8 tlirougii theiring- 14. In order to clear axle 9, saidarm isformed 'as a frame-like member surrounding said axle; and the sides 48 o'f said arm are pivotallyconnected by pins49 to: front pressure plate 13, said 1 pins passing" through the" mentioned pivot bea1ings'29a'in tlie brace 28.

Said boss 47 "is provided on one side of" a'xl- 9" and. onith'e opposite side; said arm 45 is provided-'with aneaf or lug 50.

Either: compressed air or suction maybeused to move merits of the-brake; 'cons'isting'of the plates 1'0 and 13;

thediscs 16 and 17, and the'ring "14in thelni'ann'ershowm,

thatis; in a non-engagingrelation,itwilIbe-clearfthat' a.

' pull on rod 51 toward the left willrocliarmAS on its pivot-in the same direction. By means oifilthe connection- 49'withiflie front plate, said arm draws said-plate towardZ the left-to produce frictional engagement among thezbrakeelements; It-will -be-noted that whe'ri thebrakingi power is= applied, the ful1':1ength of-arm':is used, iatid' 7 that this force is increased by1the shorter lever between pivots 46 and 49. s r

nut 58 movides a single element for adjusting the i clearance among the" brake-elements:- SH'oi-teniiig' tlie' -effctive length ofrod 51 redncesbrakeetearahee ah cr length said rod' increases such clearance? The surfaces 22, 26, 29 and 30 are preferablyprovidefi aug inarty dispesed greeves s ytharrender said 8111- 75' faces self-cleaning of road dust, particles of brake lining, etc. that-may tend to accumulate thereon. Said groovecomprises part of the air cooling means 21 but serves as exit passages for extraneous particles.

While the foregoing illustrates and describes what is 1. brake comprising a rotationa-lly mounted housing drum, two spaced brake discs rotationally carried by the drum, means connecting said discs and said drum i and slidingly engaged with the inner face of said drum,

a non-rotationalbacling plate onone side of-bn'e of said brake discs, a pressure' plate on the opposite side'ofthe' otherbrake disc, a center ring between the discs, liiili means non-rotationally connecting said center ring and the backing plate and the center ring and the ressure plate, and means pivotally mounted on the backing plate" and" connected t'o the pressure'plate tomove and press Y the lateral'faces of said plates, ring anddisc-s togethertd" arrest" rotation of the housing drum:

2 A' brake according to 'claim- 1: thelinks being later:

ally resilient and normally spacingiliecenter ring from" the backingplat'e" and the pressure plate to freely aCCbfiI-f i mo'date the brake discs 'tlierebet'ween, andtIieni'eiitioned movement of thepressu'r'e plate flexing the'linksla'terall'yi' 3. A brake according to" claim 1: the housing b'eingformed to'have' air-scooping means that draws air into said 'drumduring rotation thereof, said air circulat ing between the faces of th the late the" center and-the brake discs, said ring beingprovided'withair outlet passages, and saidliousing drum-also beingprovidedwitli" air outlet passages aligned" with said air outlets in the centerring: p g

4'2 brake according 'toclaiin l said conneetin'g'meansl' comprising" splines providedon" the" outer peripheries of said discs, and said housing drum being. provided With splin'e seats to slidingly receive said splines so that said discsro'tate'withthe housingdrum'; v 5. A-brake'according'tdclairn 1: the housing'fdrumbe iiig-form'ed to have ainscoo'ping means that draws 'air' 1 to said diiring" rotation thereof; said air circulating amon the" taces ofthle two plates,. the center riiig" and tlieibrake discs; andeir outlet assa esin the center' thg' andinthe Housing drunrportion aligned with s'aid center ring; thetwo plateshaviiig sub'stantiallyfinflxible ross: sectional form; and the'pressure plate having'cir'ciilar ribs which; in addition to stifi'eninfgsaid' plate, effect a dri'c'al tin e, two Brakedisesmeuntedwithiir saieid'rum' means connecting saiddi'iuin: and" said discs; said means comprising splines locatedfinbetween said' flange "and the peripheries of said discs,- alfiiiedbackin'gplateoii one side of one b'rake disc, a. ressure" plate on" the opposite side ofttte'eflierbrake disc, acenteniiigbetween the discs, 1

an arm pivotally. mounted onthebaclingfplate-andconneet'ed to the pressure plate' tb move the" Same. toward the backing, plate and, thereby, presssaidpltes, discs and ring'together'; and link mans interconnectin said plates and centerririgto non-rotationallyliold'tlie pres: sure pl 'ate" and" center ringdiiring' lateral movement fliereerby said'arni; a

7 A brake comprising! ii rotationally.irnounted 'hoiisingg twoispa'eed'ihrake discsrotatiohally'.carried/bysai drain"a'nitpi-n'viderr 'n'their outer gerinlieris -w itlisplines;

saic'r han ing using; provided Wiflfspfifie seats is hear exchange with the air cii'culating in the housing? tea-misebr'ake comprising a drum lia vit'i'gfcyliii; f

slidingly receive said splines so that said discs rotate with said drum, 2. non-rotational backing plate on one side of one of said brake discs, a pressure plate on the opposite side of the other brake disc, a center ring between the discs, link means non-rotationally connecting said center ring and the backing plate and the center ring and the pressure plate, and means pivotally mounted on the backing plate and connected to the pressure plate to move and press the lateral faces of said plates, ring and discs together to arrest rotation of the housing drum.

8. In a twin-disc brake the combination comprising a backing plate adapted to be fixedly secured to an axle, a movable pressure plate spaced from said backing plate, an arm pivotally mounted on said backing plate and pivotally connected to said pressure plate, a pair of brake discs concentric with said plates and mounted therebetween, a center ring mounted between said pair of brake discs, means linking said center ring with said plates and holding said ring and said plates out of engagement with said brake discs, and means to pivot said arm to bring said ring and said plates into engagement with said discs.

9. In a twin-disc brake according to claim 8: said arm comprising a frame-like member surrounding said axle and pivotally connected to said backing plate on one side of said axle, a pair of pivot pins on two sides of said arm,

said pins providing a connection for said pressure plate, and a lug on said arm on the other side of said axle from said connection to the backing plate, said arm pivoting means being pivotally connected to said arm by said lug.

10. In a twin-disc brake having a backing plate fixedly secured to an axle and a pressure plate pivotally con nected to said backing plate, the combination comprising a pair of brake discs mounted concentric to said plates, a center ring mounted between said pair of discs, said ring having a plurality of bosses extending outwardly on each side thereof and each of said plates also having a plurality of bosses spaced out of phase in relation to the bosses on said ring, and a plurality of links connecting the bosses on one side of said ring with the bosses of the backing plate and connecting the bosses on the other side of said ring with the bosses of the pressure plate.

References Cited in the file of this patent UNITED STATES PATENTS 2,015,729 Robbins Oct. 1, 1935 2,266,059 Milan Dec. 16, 1941 2,304,368 Milan Dec. 8, 1942 2,466,990 Johnson et a1 Apr. 12, 1949 2,655,227 Eksergian Oct. 13, 1953 

